The polarising ability of which one of the following is highest?

The order of covalent character of $KF, KCl, KI$ is

Which metal halide is insoluble in water?

Which of the following order is incorrect?

Arrange the following in the decreasing order of their covalent character:
$(A)$ $LiCl$ $(B)$ $NaCl$ $(C)$ $KCl$ $(D)$ $CsCl$
Choose the most appropriate answer from the options given below.

Choose the correct option from the following regarding the covalent character of compounds.